Most articles about link building  focus on quality, quantity and relevance of links, and they generally draw the same conclusion: that value and relevancy trump volume.
But rarely do I see link builders discuss link diversity for creating a "natural" link portfolio.
Certainly, link quality and quantity (to a lesser degree) play a big role in keyword rankings , but so too do the variety of links in your portfolio.
Link diversity impacts a number of different factors related to your site:
- Sphere of influence – more links from a range of websites signals more trust and authority
- Traffic mix – links from a variety of sites create new, different traffic opportunities for your site
- Broader visibility - more links across a range of sites exposes your brand to a wider audience
- Authenticity - nothing looks as artificial and manipulative as a bunch of deep links from the same website
We’ve all heard the metaphor that links are votes, ie one site’s endorsement of another. Just as a political candidate with a suspicious number of votes might be flagged for fraud, empirical evidence (and logic) suggest that Google tries not to “elect” sites with questionable linking patterns (the election here being to top query rankings).
Point being, showing relevancy to a myriad of sources is far more influential than being relevant to only a handful of sources.
Link Diversity is Insurance Against the Unknown
Nobody outside of Google knows for certain what lurks inside the Google algorithm. And nobody knows for certain what the future holds for linking signals. So link diversity is a sort of hedge against the unknown, similar to having a diverse portfolio of stocks. By keeping things varied, you’re protecting your site in case Google changes the rules and marginalizes certain links, certain sites or linking patterns.
In addition, link diversity is just common sense. Logic dictates that seeking out, obtaining or building links from the same sites, over time, has diminishing returns. The Google algorithm is sophisticated enough to recognize suspicious linking patterns and discounts inbound links from the same sites to the same deep pages, thereby negating any impact of link building. Diversity in link building solves that problem.
How to Diversify Your Link Portfolio
The obvious way to diversify your link portfolio is to get links from a variety of sites. Isabel Rodrigues from Apollo Hosting has put together a nice list of sources to consider for diversification , which I thought worthy of reprinting.
- High authority sites within your niche
- Low authority sites within your niche
- High authority sites outside of your niche but related
- Related low authority sites outside of your niche
- Social bookmarking sites
- Web directories
- Blog directories
- Blog comments and trackbacks
- Forum participation
I would add to the list that you should target both followed and nofollow links from blogs and bookmarking sites as well. Granted, they don't pass any link juice, but this tip is more about passing the sniff test and looking natural than it is about a grab for juice. Additionally, the right nofollowed links can drive traffic and provide you with another quality signal to send to Google via the toolbar and Google Analytics.
So Are You Diversified?
The ingredients of a strong link portfolio are link quantity, quality, relevancy and diversity. But not enough attention is paid to diversifying link patterns to appear authentic. Empirical evidence and common sense show that acquiring links from a variety of sources has a beneficial outcome.
Let me close by saying I know firsthand that acquiring and managing a really diverse basket of links isn't easy. Targeting hundreds of pages for deep link building and trying to keep everything straight and avoid redundancy is complex and often confusing. The key to managing link diversity is organization. Keep a detailed log of your link efforts and link acquisitions, including link sources, link targets and link text.
More on Link Diversity, Link Building
Check out this great wiki for link builders from TextLinkBrokers.com: Link Building Wiki